An Infrared Spectroscopic Evaluation of the Petroleum Potentials of Some Oil Shale From Lokpanta in the Lower Benue Trough of Nigeria

Abstract

The kerogen of thirty randomly sampled outcrops of Lokpanta oil shales in the Lower Benue trough of Nigeria was extracted, isolated and characterized by infra-red {IR} spectroscopy. Quantitative assessment of the kerogen concentrates was made and correlated with the total organic carbon content {TOC} of source rocks The isolated kerogen concentrates were found to have a mean weight [ + standard deviation] of 3.86 + 0.84% of the dry rock sample. Analysis of the IR spectra was carried out both qualitatively and semi-quantitatively. Extrapolations from structural elucidation revealed that the Lokpanta facies contained few mono-aromatics and cyclohexyl rings. The spectra variously showed good correlations in the 1600cm-1, 1450cm-1 and 2900cm-1 peak areas. Deduction from results show that although kerogen concentrates varied from 0.76% to 11.06%, over 50% of the sampled outcrops had a percent weight > 2.5% which is the lower limit proposed for mature, oil - and gas - generating organic matter.


(Journal of Applied Sciences & Environmental Management: 2002 6(1): 34-38)